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2
votes
1answer
12 views

Did astronauts and cosmonauts headed to the Mir space station go into quarantine before launch?

Humans headed to the ISS go into quarantine for 2 weeks before launch, and if they have medical problems during that time the backup crew takes over. Was this procedure also applied when going to the ...
3
votes
0answers
28 views

Falcon 9 Nozzle and Engine

From what material the merlin engines and nozzles of it (sea level) are manufactured and using what processes. I am specifically interested in the alloy used to build the engine, also about the nozzle-...
5
votes
0answers
29 views

Starship Flame trench

During static fires of the Starship engines the exhaust goes everywhere creating a dust cloud, hitting everything with sand. Why does Spacex in Boca Chica not have a flame trench at the Starship test ...
1
vote
0answers
17 views

Would the Yarkovsky effect ever be faster than a solar sail from a 1 AU orbit to the Sun?

Previously I'd mistakenly asked Would the Poynting–Robertson effect ever be faster than a solar sail from a 1 AU orbit to the Sun? when I'd meant to ask about the Yarkovsky effect which can be much ...
2
votes
0answers
22 views

Crew dragon falcon 9 first stage shut down

Crew dragon falcon 9 first stage shut down around 6700 km/hr and starlink shut down around 7900 km/hr, but around the same time. Is this because the crew dragon weighs more?
3
votes
1answer
46 views

Orbital Rendezvous vs Hohmann Transfer

Let's assume that a spaceship (capsule) is about to dock to the ISS the distance between spaceship (capsule) and ISS is 20 meters the relative velocity between the spaceship (capsule) and ISS is ...
3
votes
0answers
18 views

Do non-American space travellers train on Dragon capsule as well?

Soyuz is a spacecraft which still uses technologies from soviet era. The Dragon capsule is state of the art with its electronic upgrades. With Russia and US sharing the International Space Station ...
-1
votes
0answers
8 views

DEM generation in PhotoMod using Ground Control Points from another raster image

PhotoMod (1 2) is a piece of Photogrammetry software that can be used to process satellite images. I've just started using it and I would like to apply it to satellite imagery as reference to extract ...
2
votes
0answers
13 views

How did Osiris-Rex enter orbit around asteroid Bennu?

Bennu became the smallest and probably least massive celestial body orbited by a probe. Its surface gravity is 6 micro-g (= 6 millionths the gravity of Earth) according to Wikipedia. How did a probe ...
-2
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1answer
35 views

stage 2 possible hollow cylinder design

Stage 2 landing is considerably more difficult than stage 1 landing. There is a 1:1 payload penalty in stage 2 as compared with 5:1 in stage 1. Also, stage 2 travels at 8km/sec vs 2.5km/sec in the ...
0
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0answers
26 views

Calculate Satellite ground track

I'm trying to find equations to calculate satellite position based on orbit parameters and given time. What I currently have is a mess that is basically giving me bunch of garbage. What is latitude ...
5
votes
1answer
56 views

Is the Falcon 9 second stage engine throttled down to limit maximum acceleration

Is the Falcon 9 second stage Merlin vacuum engine throttled down during its burn to limit the maximum acceleration experienced by the Dragon or Crew Dragon capsule? As the second stage consumes ...
6
votes
1answer
258 views

What happens to orbit after a radial burn?

We know from Hohmann-Transfer or bi elliptic transfer maneuvers that a burn in the tangential direction of an orbit changes the radius of the orbit. But what happens to an object in orbit, when there ...
4
votes
0answers
36 views

What is the speed of crew Dragon upon splashdown?

After reentry, what is the speed of the Dragon 2 capsule right before splashdown? What g-force is received upon splashdown? At the time of writing, this answer gives such information for many other ...
1
vote
1answer
40 views

Would a long-term network of relay satellites but worthwhile for interplanetary communication? [duplicate]

Communication rates with probes in the outer solar systems are extremely low (Voyager is ~160 bps), because of the inverse square law and the extreme distances involved. Achieving these rates ...
5
votes
3answers
940 views

Is Crew Dragon flawed? Is it just an improvisation with no future?

I know that, Crew Dragon was initially designed for vertical landing on solid surfaces, as a reusable spacecraft, and then some changes were made to make it capable of landing in water using ...
2
votes
1answer
29 views

When is the next Transit of Venus from Mars?

When will the next transfer of Venus take place from the perspective of Mars? Will the next human to view one be a Martian?
0
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0answers
25 views

Implications of Visiting of Super Earth on Time Due to Gravity [closed]

I love when science fiction stories, movies, and shows are written with careful deliberation to ensure compliance with the most currently accepted laws of physics (inertia, stellar distances, etc.) ...
0
votes
1answer
47 views

Could a skyhook be used to change a satelites orbit from polar to equitorial?

Could this work if the skyhook also had ion engines to maintain its orbit or would the cable just snap?
3
votes
0answers
68 views

What became of slowing down and recovering the falcon 9 upper stage using large balloons

On 16 April 2018, Elon Musk posted on twitter This is gonna sound crazy, but … SpaceX will try to bring rocket upper stage back from orbital velocity using a giant party balloon And then ...
2
votes
0answers
61 views

What's the minimum speed for a spaceplane to reach outer space?

From a realistic point of view there must be a minimum speed in order to reach space in a suborbital spacecraft, let's say in a spaceplane. Like there's a first cosmic velocity (for orbit) and a 2nd ...
2
votes
0answers
28 views

What does a typical delta-v budget look like for a LEO satellite?

In terms of launch, initial orbit correction, stationkeeping, deorbiting, etc. for a typical 100-200 kg LEO satellite? Is there any source online with specifications for non-private Earth-orbiting ...
4
votes
2answers
148 views

Technical challenges recovering Falcon 9's second stage this way?

The Falcon 9's second stage is currently disposed of each flight. I know there have been some concepts by SpaceX on making it reusable, but evidently they have not yet done so. From my understanding, ...
3
votes
1answer
66 views

Are there any images of SOOS?

SOOS--Stacked Oscar On Scout--was what it was called when the 1985 decision was made to replenish the Operational (Oscar) Transit constellation with unflown first-production models. Early Oscars were ...
2
votes
1answer
130 views

Why are the Falcon 9 Stage-1 engines placed with offsets in the octaweb compartments?

Pictures of the octaweb show that the engines are not placed at the center of each octaweb compartment---they are closer to one side than to the other. See the picture below for an example. Focus on ...
2
votes
0answers
102 views

Did Zuma really fail? Did it complete at least one orbit?

Zuma bumped NASA for the first launch of 2018 but the mission's status remains murky. Wikipedia says: The US government has not publicly stated if there was a failure of Zuma and this secrecy has ...
4
votes
0answers
30 views

Book Recommendation on History of Spaceflight

I'm a CS/Engineering student at CalTech and I'm searching for a book that can help me better understand the history of spaceflight and the problems associated with getting humans to space. Since this ...
9
votes
1answer
127 views

Can Crew Dragon land with more people than it was launched with?

For example, Crew Dragon recently delivered two astronauts to ISS and there are at the moment 5 astronauts on board ISS. Assuming [pick your own disaster scenario] happens and all 5 astronauts had to ...
12
votes
1answer
116 views

Were Crew Dragon's touch screens tested under 3-5 G on Earth in a centrifuge?

To use a touch screen wearing a pressurized suit with gloves may be not as easy as without space suit and gloves. But what about tests done under more than Earth's gravity?
3
votes
0answers
44 views

How could the landing date of Perseverance Rover be fixed irrespective of 26 days launch window?

I am very much aware of this question from 2018 by @uhoh - Why would InSight's arrival date at Mars be fixed, and independent of the launch date?. I was led here by a similar question which arose in ...
4
votes
0answers
38 views

What were the earliest rocket payloads (US and Russian) that supported coasting at anywhere in the ascent?

I know that sequential staging of rocket boosters was problematic, leading to Atlas stage-and-a-half and Russian hot staging. At what point did rocket boosters have attitude control allowing them to ...
-8
votes
0answers
36 views

For any Mars Station to work we need to build a dedicated 100% sustainable survival pod NOW! [closed]

We are creating a project in Antarctica to simulate life on Mars or the Moon. We are a global group of concerned citizens from all nations. I am new to this group so Im coming straight to the point. ...
1
vote
0answers
72 views

Would ICBMs be visible?

Simple question really - would ICBMs be visible to a person from the ground on a clear night, in much the same way the Starlink satellites have been? Edit - to be clear, I'm meaning when the warheads ...
3
votes
0answers
59 views

Is the outside surface temperature of a Falcon 9 below freezing? How is the LOX insulated?

This answer explains how the liquid oxygen in a Falcon 9 is evaporation cooled to maintain a temperature well below boiling, by bubbling helium through it. The temperature difference to the ...
3
votes
1answer
94 views

Why was there never a lander for the Martian north polar cap?

Since the Martian poles are water ice caps, belong to the most likely locations on Mars to host life, and the north pole being the most likely place for a crewed mission, it seems reasonable that one ...
1
vote
1answer
43 views

How are orbit insertion changes in altitude and RAAN designed?

Assuming that desired inclination is achieved during the launch, how are the target altitude and RAAN usually achieved in satellite missions, if the launch could only place the satellite on a ...
5
votes
0answers
118 views

Will Soyuz spacecraft be able to visit the Lunar Gateway?

I mean launch from Earth, dock to the gateway and come back.
8
votes
0answers
139 views

Will SpaceX paint over the NASA Worm on booster 1058 for its next flight?

For the Dragon Crew mission SpaceX flew a brand new booster (how declasse) B1058 and painted it with the old style NASA Worm logo. SpaceX owns the booster and is most likely to fly it many more times ...
3
votes
0answers
60 views

Kinematic and Dynamic viscosity on Mars

I've been looking at the Mars helicopter (Ingenuity) that will be onboard the Mars 2020 rover and I am having trouble figuring out how they determined the size of the rotor blades. Specifically, I'm ...
-1
votes
0answers
75 views

Type of Antennas used by SpaceX

What kind/variation of Antennas are used by SpaceX and how many in Falcon 9 Rockets for the precise landing of the rocket? I don't have any kind of knowledge in antennas and communication systems ...
4
votes
1answer
134 views

Do converging-diverging engine nozzles need to be bell-shaped?

Many rockets designed after the V2 but prior to Saturn V, do not show the typical "Bell" shaped diverging nozzle. Why is it so? Do they achieve supersonic speeds for the exhaust gases in any other way?...
-3
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0answers
63 views

Design of rocket engines [closed]

2: Is there any site which has details of "technological developments" in designs of rocket engines, recorded chronologically?
-2
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0answers
54 views

Rocket engine development [closed]

1: While German v2 might have been the base reference for future designs of rockets, many rockets do not seem to have used the "diverging" nozzle, at least their photographs do not show the "Bell" ...
2
votes
4answers
184 views

Have space probe gone to unplanned destinations?

Reading this question about multiple gravity assists (Why is Voyager 1 faster than all other space probes?), it caused me to wonder if any probes have been redirected to additional (or alternate) ...
6
votes
1answer
137 views

What were the space shuttle’s emergency procedures for an SRB or ET separation failure?

The space shuttle, like most launch vehicles, was a multistage vehicle (albeit one where the various stages were mostly stuck to the sides of each other rather than being stacked vertically), reducing ...
5
votes
1answer
151 views

Are deployed astronauts (e.g. on their way to or already on ISS) notified if something of importance happens to one of their family members?

The question is sparked in part by the "America's favorite dads in space" narrative which accompanies the recent Demo-2 mission, involving astronauts Rob Behnken and Douglas Hurley, as well as their ...
26
votes
3answers
5k views

Why does NORAD make TLE data public?

If I understand correctly, NORAD tracks thousands of satellites as well as pieces of space debris and publishes TLE files representing their orbital position and motion that are updated regularly. It ...
5
votes
1answer
150 views

Purpose of foil on Merlin Vacuum Engines of SpaceX

I want to know what is the purpose of this silvery foil situated above the bell in Merlin Vacuum Engines, and what purpose does it fulfill exactly?
17
votes
2answers
3k views

Where will the Pioneer, Voyager and New Horizons spacecraft be after one galactic orbit?

After the Pioneer, Voyager and New Horizons spacecraft complete one orbit of the Milky Way (in approx. 230-250 million years or one "galactic year"), how close will they then be to our solar system? (...
10
votes
1answer
835 views

Falcon-9's subcooled LOX is continuously refrigerated in-situ, what about its subcooled RP-1?

@Uwe's answer to Why would sub-cooled LOX tanks need to “topped-off” until the last minute or so? explains how subcooled LOX is kept cold and dense by "in situ refrigeration"; helium is bubbled ...

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